Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd45c3474e653bf4cddd3361dd43eecc00b39416a4853e9c0b5239967474fb3e' 
  AND token = 'mUQOL2DGqIEmkhFrodeWkHnW70ddNxMWm9GwbWDb97k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}